The Atomic Bomb Dome still stands today to commemorate the dropping of the first atomic bomb.  That bomb killed 140,000 Japanese civilians, and turned the city into a blackened wasteland.  Every building was flattened except one.  Pictures of Hiroshima after the bombing show just a single building standing, the skeletal frame of a building with a dome.

The shell of that domed building was intentionally preserved in the the state immediately after the bombing, and eventually came to be called "Atomic Bomb Dome" and has since become famous as a symbol of Hiroshima.  In 1966 the City Council adopted a resolution to preserve the monument for posterity and in 1996 the dome was registered on UNESCO's World Cultural Heritage list as a monument that reminds us of the tragedy of the bombing.  The structure is now the centerpiece of Hiroshima's Peace Park.

Before WW2, the building was The Hiroshima Prefectural Industrial Promotion Hall.  It was a European-style building with an oval dome and wavy walls and had long been a famous attraction of Hiroshima City.  Less well-known is that it was the work of a Czech architect, Jan Letzel, who spent much of his life in Japan.  His design had combined the styles of neo-Baroque and Art Deco and was completed in 1916.